| Country: | Thailand |
| Previous Election: | 1937 |
| Next Election: | 1946 |
| Seats For Election: | 91 of the 182 seats in the House of Representatives |
| Election Date: | 12 November 1938 |
| Turnout: | 35.03% |
| Nopercentage: | yes |
| Noleader: | yes |
| Party1: | Independents |
| Seats1: | 91 |
| Last Election1: | 91 |
| Prime Minister | |
| Before Election: | Phahon Phonphayuhasena |
| After Election: | Plaek Phibunsongkhram |
General elections were held in Siam on 12 November 1938 to elect 91 members of the 182-seat House of Representatives. The other 91 members had been appointed by King Ananda Mahidol after the 1937 elections.[1] At the time there were no political parties,[2] so all candidates ran as independents. Voter turnout was 35%.[3]